Subodra - The Coding Gawddddd is doing research on nuclear bomb . She want to create a huge Nuclear bomb from small bombs . This huge bomb is known as Subodram For creating a huge bomb , she can use at most three small bombs

-> The Power of huge bomb is product of small bombs.

Can you tell the maximum power of huge bomb ?

Input:

First line contains n, the number of small bombs. Next line contains power of N small bombs separated by space.

Output:

maximum power of huge bomb

Constraints:
1 ≤ N ≤ 100000
0 ≤ power of each small bomb ≤ 1000000

Setter : Subham Gupta